1. Field of the Invention
The present invention relates to an improved carbon monoxide monitoring system and, more specifically, to such a system that conditionally opens a motorized garage door at the times that carbon monoxide levels, as controlled by the presence or absence of smoke, reach unsafe thresholds.
2. Description of the Related Art
U.S. Pub. No. 2005/0,212,681, to the present inventors, discloses a garage monitoring system that includes a carbon monoxide (“CO”) detector and smoke detector that generates an audible alarm when it senses CO and/or smoke at a predetermined level. There is presently no similar system that is incorporated in or works in conjunction with a standard, motorized garage door assembly.
The garage monitoring system also includes a method of determining if the garage door is opened or closed. This is necessary because the system will not issue a move door command if the garage door is already opened and it will not issue a move door command if smoke is detected first.
A carbon monoxide and smoke detector placed in a garage or a similar space has been a controversial, but a desired, feature considered to enhance a home or business' safety for many years. To enhance safety, the system will have terminals to which remote alarm can be sounded or a security system notified. To assist in determining the cause of high CO levels or smoke, the system will internal store the order of the alarm sequence (which came first, smoke or CO) and data about the concentration levels if that can be extracted from the sensor modules.
Optionally, the system may have an external carriage that accommodates garage door systems that are not activated by a wired wall switch. This is referred to as RF (Radio Frequency) only garage door opening systems. The carriage would contain the garage door opener that came with the garage door. If a garage door move command is issued, a motorized cam assembly would “press” the garage door opener's switch thus opening the door. The system could therefore be interfaced to almost any garage door opening system.
The alarm would be a sounding device that meets the loudness requirement standard and may include a light and/or voice enunciator.
The system may include a heater that helps to keep the smoke and/or CO sensors within their designated temperature range.
The system may include indirect methods of fire detection by setting a maximum temperature and/or rate of temperature change and/or infrared signature to initiate an alarm. As stated previously, in this circumstance the position of the garage door would not be changed.
The system may include indirect methods of CO detection that include the identification or periodic sounds made from running cars, lawn mowers, etc. A circuit would be included to determine if the sound origination was inside or outside of the garage.
The system will use a switch mounted on the garage door rail or some other place on the garage door assembly to determine the position of the garage door. Optionally other methods to determine the position of the garage door may be used, such as ultrasonic and/or infrared reflection techniques.
The system may contain batteries to operate during commercial power failures.
The system electronics may optionally have a timer that will indicate when the smoke or CO's sensor has reached end of life.
The present and the improved monitoring system provides the foregoing advantages by means of the emergency interface and the smoke detector. The present invention further improves home and business safety through early detection.